Evaluation of superabsorbent polymer on leaf area index, relative leaf water content and growth rate of sesame under water deficit stress condition

Drought is one of the most important problems of crop production in arid and semi-arid regions of the world. The application of some materials, such as superabsorbent polymers in the soil, increases the water retention in the soil and thus reduces water consumption and leaching of fertilizers, therefore is one of the best solutions for water management in water deficit conditions. This study aimed to investigate the effects of superabsorbent on some characteristics of sesame under different irrigation intervals. This experiment was performed in a three replicated-split plot factorial, arranged in RCBD with three drought factors as the main plot (Irrigation interval using cumulative evaporation from class A pan: 80 mm (I₁), 160 mm (I₂), and 240 mm (I₃), and superabsorbent (SAPs) Stockosorb in three levels (0, 100, 200 kg ha^-1) (Z₀, Z₁, Z₂) as the subplots. The results showed that water deficit intensively decreased relative water content (RWC), Leaf area index (LAI), and crop growth rate (CGR) in both mild water stress (I₂) and sever water stress (I₃) compare to normal irrigation (I₁). SAPs mitigated the adverse effects of water deficit by improving RWC, LAI, and CGR. Due to the problem of water supply for plants in arid semi-arid regions, the use of 200 kg ha^-1 superabsorbents with 80 mm evaporation from class A pan be recommended as a successful method to maintain moisture and increase the growth and development of sesame.